Against the background of possible substantial sea‐level rise, an important question is, how and to what extent coastal societies are able to adapt. In the current climate change literature, answers to this question mainly come from a sea‐level science perspective.

This talk will address this question by integrating perspectives from coastal engineering, economics and social sciences to comparatively analyse a set of diverse cases from around the world in terms of their technological limits, benefit‐cost barriers, financing barriers, and social conflicts. Across the cases, it is found that the ability of societies to adapt to 21st century sea‐level rise is not constrained by technological limits. In some cases, adaptation involves engineering challenges, but these do not constitute limits, but will make adaptation more costly. Regarding economic barriers, we see a divided world. On the one hand, there are densely populated urban areas, for which it is highly profitable to protect against rising sea‐levels. On the other hand, protecting rural areas and agricultural land is generally not profitable. But even when profitability is high, coastal adaptation is frequently constrained by inaccessible finance. One reason for this is that coastal protection projects involve high up‐front investments, while the benefits are stochastic and occur over a long time horizon. Social conflicts are present in all cases. The reason for this is that both sea‐level rise and coastal adaptation massively redistribute risks and benefits amongst stakeholders, which means that there will be winners favouring adaptation and losers objecting.

These findings call for expanding currently underdeveloped coastal social science adaptation research in order to address financial barriers and social conflicts. This should include research on cooperation and governance arrangements for reconciling conflicting stakeholders' interests, distributional and equity issues between winners and losers of SLR, and financial arrangements for bridging the gap between high up‐front investments and stochastic long‐term benefits of adaptation.